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Description of ball lightning in the 1900s........ It originated as one ball, but on touching the ground split into two. These rose and while one went down the chimney of a house and exploded, doing great damage, the other followed a more erratic course. It went down the chimney of another house, crossed a room in which were a man and child, doing no harm to either and then, making a small hole in the floor, went through into the chamber beneath, used as a sheep fold. Five older sheep were killed and the ball passed out at the doorway. The shepherd's son at the door was not injured. |
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WEIRD SCIENCE PAGE database of encounters with Ball Lightning. It was 1962 and I was in Patrol Squadron Four in the U.S.Navy station on temporary duty on Adak Island in Alaska. The story was told to me and confirmed by fellow crewmen of the Tactical Commander of one of our planes ASW stations. The crew of a P3 Orion were on a routine flight in the Aleutians. Weather was turbulent with distant thunder. During the middle of the flight, a few hours out, a large red glowing translucent object came through the rear bulkhead of the plane near the galley and slowly "rolled down the deck" passing the tactical command center. Crewmen sucked back their feet less they get touched by it. Slowing it left through the right fuselage forward of the electronic load center. It did not damage. The Lt. Cmdr said it was the size of a basketball. It was in the plane less than a minute. Steven Salkow Pleasanton, ca USA - Friday, January 25, 2002 at 19:14:08 (PST) My family's cottage in Ontario Canada, was the last cottage on the electrical line. During the many intense summer thunderstorms my sisters and I would sit by the electical outlets and watch what I remember as blue bolts off light coming out of the outlets with each big lightning strike. There were two hanging lamps in the living room one had had some sort of electrical short a few weeks before and was damaged (not by lightning). After a big lightning strike an orange ball (sunlike) about the size of a basketball came out of the damaged lamp, moved across the room at a walking speed and disappeared into the other hanging lamp. This happened in the mid 70's and I was about 9 years old. Unfortunately the electrical line has now been extended and forms a loop. The blue zots no longer happen. Ernie Kovacs Pacific Grove, CA USA - Tuesday, September 04, 2001 at 15:02:25 (PDT) In the early 70's and in the county of Hereford in England, my sister and I were playing in the front garden and had made a tent out of an old wall and Mum's teatowels. We were quite young (5 & 6) but still remember very vividly that late afternoon the air just changed and an almighty thunderstorm came over really quick. We were very scared and huddled behind the teatowels but then all of a sudden a bright light brought us out and in front of us there was ball of flame the size of a beach ball. It seemd to hover in front of us forever but probably not even seconds. I was going to touch it as I thought I saw the face of Jesus in the ball. Lucky my elder sister grabbed my arm and stopped me otherwise I probably wouldn't be here today!. The ball then just shot off and disappeared up into the sky. Yvonne Watts Essex, England - Saturday, August 18, 2001 at 11:02:50 (PDT) Summer 1969. It was another terrifying Florida electrical storm. The mid and late 1960's seemed to have more vicious lightning storms in number and closeness, then the 1970's, 80's or 90's. I think it was related to more cold air aloft intrusions then we have experienced since. When you have a 500mb temperature of -10 Celsius or colder here in Florida during summertime it contributes to a high lightning strike frequency. I was in the kitchen of my parents home. I observed lightning strike an oak tree ( rare) in our back yard. A second later a ball of lightning (plasma) about the size of a basketball and as bright as an arc welder, rolled off the tree about 6 feet off the ground. The ball made a loud buzzing sound as it slowly moved towards and hit our large in wall air conditioning unit, knocking it out. My mother saw a blue flame shoot out of the air conditioner about 6 feet long. The ball then moved onto the chain link fence in our back yard, accelerated and hopped succeeding chain link fences for about 2 blocks. The ball then ran out of chain link fence where it terminated at the corner of a neighbors stucco and block house, blowing a very large hole in the house. As the ball traveled through the neighborhood, it also knocked a man off of his porch swing, causing minor injury. Thomas Giella Plant City, FL USA - Saturday, July 21, 2001 at 13:16:58 (PDT) Ball Lightning. Time 3:45 PM October 30 1996. Place road to Wombian Caves Mittagong NSW AU. Conditions: Overcast, very dark sky, rain iminent. Travelling from the caves to Mittagong I was in a convoy of 4x4s behind a ford ute. The ute suddely veered off the road and bounced off a few trees to the left. The White Landcruiser in front veered right and around the ute. I noticed a bright orange glow which was north (right side of the road) and turned to look. Travelling 5-6 foot above and parallel with the ground near a vehicle recess in the 4 wire fence was a glowing ball about the size of a soccer ball (about 10 inches) in diameter. It was moving in a direction parallel to the road (and fence line) at around 30 MPH. It was strangely deliberate in it's movement, and unaffected by the raging winds. It was not raining at that spot on the road though it was raining just previously on the same road. The ground was a little wet where we saw the ball, but not raining. It was the same colour as a sodium lamp. No loud noises were heard other than my engine which never faulted. The ball was around 20 foot away from the car. It lasted around 10-15 seconds. Garret Krampe Ashfiled, WA AUSTRALIA - Sunday, July 08, 2001 at 06:55:04 (PDT) Plant City, FL USA - Saturday, July 21, 2001 at 13:16:58 (PDT) Pleasanton, ca USA - Friday, January 25, 2002 at 19:14:08 (PST) In 1943, I was taking a bath in an old metal wash tub on the farm when a hugh sky to earth lighting storm began. This was in southeast Kansas. I thought nothing of it until a large orange ball of light came through the window that I had the blind pulled and it only took a brief second for the ball to hit me. I was so frightened that I though that I was dead. I remember jumping up and running into another room. There was a red mark on one leg and the opposite arm where they touched the metal tub. It took at least fifty years for me to be able to relax whenever it rained. Prior to that I would break out in a sweat and could hardly relax until the storm was well over and gone. The only thing I could think of was "ball lighting", but I could never find out anything about it until I check this web site. Ball lighting or just lighting? Richard Harris Wichita, Ks USA - Tuesday, June 19, 2001 at 16:00:26 (PDT) Ball lightning is definitely real. In the summer of 1975 I was almost eight years old, and I was living with my grandparents in Clearwater, Florida, which gets severe thunderstorms from the Gulf of Mexico and Tampa Bay ("most lightning strikes in the USA"). The usual summer afternoon thunderstorm was raging, and then suddenly we heard a loud KABOOM from the back yard. My grandfather, grandmother and I ran to look out of the back window, and there were several glowing yellow-orange balls of light bouncing down the main transformer pole at the side of the yard, which had apparently been hit. As we watched, they came down the pole onto the ground, and bounced away in formation around the side of the house toward the front yard, out of sight. We ran to the front window. They came out of the side yard, still bouncing gently, and -- this is where the really weird part starts -- they hit the sidewalk, turned left, and went straight down the sidewalk past our neighbors' houses until they were out of sight. (We were all bug-eyed; I wanted to go out and play with the bright balls, but my grandma wouldn't let me!) As we all stood there talking about what we had just seen -- they came back! At some point, out of sight, they must have stopped on the sidewalk, turned around, and started back the way they came, because there they were -- coming back down the sidewalk, still slowly bouncing in single-line formation, and this time they continued down the sidewalk past our house on the right until we lost sight of them again. It seemed as if they had some type of primitive awareness, so that they could actually travel and turn around on a sidewalk like a group of people out for a stroll (although I'm sure there's a better scientific explanation). That was our last sighting; they didn't come back. This ranks among the most vivid and exciting memories of my childhood -- I don't remember being scared at all, just fascinated. Keri San Diego, CA USA - Monday, June 11, 2001 at 15:06:49 (PDT) The event I witnessed occurred on 4-5-01. The day was overcast and humid, and thunder was audible in the distance. I decided to take the dog for a run before it rained, and we went to a park by the river near our home. I got out of the van, and walked approximately 15 feet when I sensed something coming towards me over my right shoulder at a rapid speed. I bent down to avoid being hit, and in front of me, hovering above the ground, was a bright, white ball the size of a bushel basket. A deafening clap of thunder sounded and the ball had vanished, but the skin of my face felt stretched, and my hands were tingling. I ran for the van, and left the park with a very frightened dog. The elapsed time from entering the park, and leaving was 3 minutes. My husband and I went back to the park later that evening, and there was no evidence of lightning stike. I called the meteorologist at the weater station, and she said I had witnessed "ball lightning". Mary B. Springfield, Il. USA - Friday, April 06, 2001 at 13:33:10 (PDT) |
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This and other dangerous expts courtesy of C.Willis This is the "ball lightning" effect in the 700-watt oven in my dorm, captured
via a video camera. The ball is on the order of an inch in diameter and
glows a fiery orange / violet color. It survived about four seconds, and was
produced via Procedure 1 below...
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Any explanation of ball lightning must take into account the curious properties attributed to it by those who have
seen it. It would appear that the typical lightning ball or, to use its German name,kugelblitz is a luminous sphere perhaps as bright as a strong household fluorescent lamp. The sphere may range in diameter from a few inches up to a few feet, most often from six inches to a foot. It usually materializes immediately after an ordinary lightning stroke. The ball can be almost any color, although green and violet are rare. Most seem to shine steadily, but some pulsate. Normally the ball moves about, sometimes along a conductor or an insulator and sometimes directly through the air. It can last from a second or less up to several minutes; the median, if one may judge from the estimates of startled observers, is a few seconds. Some balls fade out; others disappear abruptly, occasionally with an explosive report. Lightning balls seldom damage anything badly, although they sometimes leave physical evidence of their occurrence. They have scorched wood and burned through wires. The matter of damage is important because some estimate of the amount of energy stored in the ball is essential to an evaluation of the various theories. Since lightning balls have not been produced in the laboratory, estimates of their energy content are based entirely on the subjective reports and on inferences from their effects. It is easy to set an upper limit to the energy stored in a lightning ball by assuming that the air within the ball is at most singly ionized. This means that each atom or molecule in the air has lost one electron and that there is an equal number of free electrons. A gas in this state is called a fully ionized plasma. In ball lightning the energy that went to ionize the air is stored in the plasma until the charged particles recombine, releasing the energy in the form of light, heat and sound. An average lightning ball 25 centimeters(10 inches) in diameter and singly ionized at normal atmospheric density would contain about one megajoule(million joules) of energy. I am indebted to M. L. Goldberger of Princeton University for pointing out to me that a megajoule can be visualized as the amount of energy released by the chemical combustion of a large jelly doughnut. In order to determine the energy content of an object the investigator normally employs calorimetry. He places the object in a known quantity of water and measures the extent to which the water is heated. The amazing thing is that just such an experiment was accidentally performed by a lightning ball in the presence of an apparently sober and reliable resident of the London area. According to The Daily Mail for October 3, 1936, the observer reported that the glowing ball came out of the sky, cut a telephone wire, scorched a window frame as it entered a room and finally dived into a butt (a small barrel) containing four gallons of water. The water boiled "for some minutes," indicating that the lightning ball must have persisted most of this time. In support of his claim that the water actually boiled, the observer testified that he could not keep his hand immersed in it 20 minutes later. To boil so much water the lightning ball must have had an energy of not one megajoule but at least four megajoules and perhaps as much as 10 megajoules. The concentration of energy in the ball must have been considerably higher than that in our 25-centimeter, one-megajoule model: the ball was said to be the size of a large orange. Several hypotheses have been suggested but non account for all the observations. Scientific American. March 1963 |
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First a bit of theory...a microwave oven is a conducting cavity that confines the 2.54 GHz energy produced
by the oven's magnetron. The magnetron is a really clever type of vacuum tube that converts DC into
microwaves with over 70% efficiency. It usually resides in the right-hand side of your oven , coupled to
a short length of waveguide that leads to the oven cavity. A typical oven magnetron develops 700 watts of power.
The waveguide that leads from the "maggie" to the oven can only propagate a single mode of oscillations- the
simplest transverse electric mode. But the oven itself is much larger than the dimensions of the wavelength of
the microwaves, and many field configurations are possible. The energy is distributed among these modes.
The fields in a microwave oven are quite high- voltage gradients of 500 V / cm exist in an average oven,
according to a book on microwave heating technology (sorry- I forgot the name!) So this makes it possible
to generate arcs and discharges with the RF power in the oven.
The reason the "ball lightning" is formed is that hot ionized gas in flames and arcs is a pretty good conductor,
and like a moist hunk of meatloaf, will absorb microwave power and resistive heating will result. Being hot and
lighter than surrounding gas, the arc or flame will rise and can detatch from its source. The resulting ball is
kept hot by continuing to absorb microwaves. When the ball reaches the metal walls of the oven cavity, its heat
is absorbed and it loses its ability to conduct. Hence the discharge is terminated. 
This is Design 1. Cut a disk "B" of aluminum or copper, 2.4 inches in diameter. Solder or tape a 1.5-inch long piece of metal sheet "A" to its midpoint, cut a sharp point at the free end, and bend it within a few centimeters of the disk edge as shown. Aluminum foil works, but it's not durable, as you can easily observe after firing the toy. If you value the nice paint job in your oven cavity, don't set the toy directly on the bottom of the oven, but rather on a glass or other standoff so it can't spark through your paint and blacken it. The toy works best if it's not rotated (disable your oven turntable) and if your oven doesn't have a "mode stirrer" fan. If it does, you can disable that also with a rubber band (find out how yourself.) This device wants a powerful oven, 700 watts or more.
Design 2. This is made from copper pipe and sheet that is silver-soldered together to make a little alcohol lamp. The dimensions of the surface "B" are the same as the dimensions of "B" on the first device, and "A" is a piece of 3/8" refrigerator tubing about an inch long. A little ethanol is poured into the lamp through the tube, and a piece of string is inserted to wick up the alcohol. Light the lamp (please make sure it is not leaking any alcohol!!!) and place in oven. The flames grow and become balls.